1. Field of the Invention
The present invention relates to an iron powder attracting magnet for attracting and removing iron powder contained in a fluid such as a liquid.
2. Description of the Prior Art
In a transmission or a differential gear to be used in an automobile or an industrial vehicle, for example, oil is used for lubrication so as to prevent a plurality of gears for drive power transmission from seizing and wearing. As the running time elapses, the gears will wear so that the resultant iron powder will mix into the oil. This iron powder will raise problems to wear the gears abnormally and to accelerate the aging of the oil. Efforts have been made to solve those problems by mounting an iron powder attracting magnet in a transmission case or a gear case which accommodates the gears and stores the oil, to attract and remove the iron powder from the oil.
As shown in FIGS. 7 and 8, iron powder attracting magnets 1a and 1b existing in the prior art have rectangular or disc shapes and are made of a sintered magnetic material. These magnets 1a and 1b have their upper surfaces 2 act as iron powder attracting surfaces to attract and remove the iron powder.
Since the iron powder attracting magnets of the prior art are made of a sintered magnetic material, as described above, they are heavy and liable to crack, chip or break. From the molding restrictions, the magnets cannot be molded into other than the simple shapes such as the rectangular or disc shapes, as shown in FIGS. 7 and 8. Thus, the magnets have a small degree of freedom of the shapes, a low sizing accuracy and a restriction upon the attracting ability.